Flame hardening head



FLAME HARDENING HEAD l 2 Sheets-Sheet l Nmn S9 E949 M. FEW

FLAME HARDENNG HEAD i2 Sheeis-Sheec 2 Filed April 7,. 1948 Patented Nov.8, 1.949

FLAME HARDENING HEAD Edgar M. Fein, Wellington, Kans., assignor toCardwell Wichita, Kans.

Manufacturing Cmpany, Inc

Application April 7, 194s, serial No. 19,503

(ci. 26e-4) l Claim.

1 This invention relates to flame hardening heads and particularly to adevice incorporating means for directing a heating flame toward a workpiece and further means for directing a quenching fluid on to the heatedwork surface. It is an object of this invention to provide such a flamehardening head wherein the work is quenched in stages.

It is a further object of this invention to provide a simple unitarystructure which includes means for heating a work piece and subsequentlypartially quenching the heatedsurface and finally completely quenchingthe surface as the work piece is moved therepast.

It is a further object of this invention to provide a method vof amehardening which produces a satisfactorily hardened surface without thesurface stresses incident to severe quenching of a heated work piece. lvFurther objects and advantages of the invention will become apparent asthe description of a preferred embodiment proceeds in connection withthe accompanying drawings, in which:

Fig. 1 is a front elevational view of an embodiment of the presentinvention as viewed from the position of the work piece;

Fig. 2 is a vertical sectional view taken substantially along the line2-2 of Fig. 1; and

Fig, 3 is a fragmentary sectional view, on an enlarged scale, of onerend portion of the ame hardening head and taken substantially along theline 3-3 of Fig. 2.

The flame hardening head of this disclosure comprises an elongatedunitary body member I having therein a plurality of longitudinallyextending and substantially parallel chambers 2, 3, and 4. Each of thechambers may be provided by milling through one surface of the member ormay be originally cast therein, or provided in any convenient manner.Each of the chambers extends through a rear wall 5 of the member I andadjacent said rear wall each chamber is somewhat enlarged as indicatedat 6. In each of the enlarged portions a closure 'l is fitted to definea completely enclosed chamber. The closures 'l are preferably of such asize as to be frictionally retained within the enlarged portions withsufficient force to withstand the internal pressures involved. The upperchamber I has a reduced portion 8 at the front thereof defining ashoulder 9 against which a baille plate III is press-fitted and providedwith a. plurality of openings II. Adjacent the middle portion of theelongated head conduit means I2 provide communication with the interiorof the chamber 2. A plurality of longitudinally extending rows ofopenings I3 extend from the forward portion 8 of the chamber u2 throughthe front wall of the unitary member, as lshown in Figs. 1 and 2,.v yTheupper chamberjust described constitutes afuel chamber. r,Thefuel isadmitted from a suitable source (not shown) to the conduit I2, .whenceit is discharged into the chamber 2 and upon passing through theopenings II the .constituent parts thereof become thoroughly mixed.Thefuel thenpasses through the openings I3 and issues therefrom in theform of jets directed toward a work surface. I It will be clear` thatwhen suchl jets are ignited avsheetof flame will be directed toward thesurface of a work piece to thereby heat the same. v

The intermediate chamber 3 is providedfwith a row of openings I4 which,like the openings I3, are directed generally towardthe, work piece. Thelower chamber 4 is provided with a plurality of rows of yopenings I5,which arefalso directed to-v ward the work piece. A conduit II which isof generally Y-shape is in communication at its forked ends with theinterior of the chamber 3 at the opposite ends thereof. The lower orstem portion of the conduit I6 communicates with a suitable source ofsupply (not shown) of a quenching medium to be supplied to the chamber3. A similar conduit I1 is arranged to supply a second quenching mediumto the lower chamber 4.

As clearly shown in Fig. 2, the front wall I8 of the member I isprovided with aprojecting portion I9 defining a ledge 20 adjacent'stheopenings I3 and a lower sloping surface 2| through which the openings I4and I5 extend. -hs shown, the openings I4 and I5, although directedgenerally toward the Work piece, do extend in a direction slightly awayfrom the openings I3. The chambers 3 and 4 will be filled with aquenching uid under pressure, and as that fluid issues from the openingsI4 and I5 it will impinge upon the surface of the work piece and aconsiderable quantity thereof will be splashed in all directions. Theprojection I9 and the ledge 20 will act to prevent the splashingquenching fluid from reaching the openings I3 and thereby extinguishingthe heating flame.

It is contemplated that the structure just described be employed toharden a work piece that is` mounted for movement past the face I8 ofthe member I in relatively close proximity thereto. In practice a hotquenching fiuid will be supplied to the upper chamber 3 and a coldquenching fluid will be supplied to the lower chamber 4. As the workpiece moves slowly past the flame hardening head it will first becomeheated by the name issuing from the openings I3 and the heated portionwill then pass downwardly tok a position where it is partially quenchedby the hot quenching fluid issuing through the openings I4. However,after this partial quenching the Work piece will still retain aconsiderable amount of heat, suicientlto'effect tempering to'relievesurface stresses that would otherwise develop if the work piece werecompletely quenched to room tempera-` ture in the first instance. Afterthe partial quenching is accomplished the work piece `moves into thefinal quenching zone, that is, to a position where the cold quenchingmedium issuing from the openings l5 will impinge thereupon and reducethe temperature of the work piece to its final low temperature.

The above described method and apparatus have been employed by using amixture of acetylene gas andV oxygen as the fuel to heat the worksurface above the critical quenching temperature and hot and cold waterhave been successfully used as successive quenching mediums. It has beenfound that a work piece that has been heattreated in the mannerdescribed herein possesses a surface hardness only slightly lessthanthat it would possess if it had been quenched in one stage with coldwater, but at the same time the toughness of the surface was increasedand the tendency to cracking minimized.

Although a single embodiment of the invention has been shown anddescribed herein it is to be understood that all modifications arecontemplated which falli'airly within the scope of the appended claim.I' claim:

In a flame hardening head, an elongated unitary member, a fuel chambertherein extendingA longitudinally adjacent one edge thereof, meansdefining a longitudinallyextending series of openings from said fuelchamber through a first eX- l terior surface of said member, a firstelongated coolant chamber in said member adjacent said fuel chamber andsubstantially coextensive therewith, a second elongated coolant chamberin said member adjacent the side of said first coolant chamber remotefrom said fuel chamber and substantially coexte'nsive with said firstcoolant chamber, jet directing openings along the length of each of saidcoolant chambers and extending from said coolant chambers through asecond exterior surface of said member in the same general direction asthe openings from said fuel chamber, conduit means for conducting a hotquenching medium to each end of said first coolant chamber, and furtherconduit means for conducting a cold quenching medium into each end ofsaid second coolant chamber, said exterior surfaces being arranged instepped relation to each other with said second surface being arrangedto lie closer 'to a workpiece than said first surface.

`EDGAR M. FEIN.

REFERENCES CITED The foliowing references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 854,810 Daniels May 28, 19071,924,099 Bain et al Aug. 29, 1933 2,224,006 Day Dec. 3, 1940 2,274,861Gridley Mar. 3, 1942 2,329,188 Denneen et al Sept. 14, 1943 2,382,515Smith Aug. 14, 1945 FOREIGN PATENTS Number Country Date 225,333 GreatBritain Mar. 19, 1924 849,306 France Nov. 21, 1939

